AMC1302-Q1: AMC1302-Q1 bias current in error calculation clarification

Tool/software:

Hello, 

We are looking into using this iso amp for power application.  I'm doing tolerance analysis on this with the given shunt. 

Could you clarify in the datasheet does Ibias for negative and positive input is in the SAME direction or can be in opposite direction. It seem to be they are in the same direction and Ios is what defines the differential bias current. Is that correct assumption?

If they are in the same direction, how internally do they play in input offset voltage contribution?

Thank you!